Query and count the borrowing situation. Dbf, which shows the book number and borrowing times of each book.
Select the book number and borrowing times from borrowing. dbf
Look up the book. Dbf, and display the information of all books whose titles contain the word "basic".
Select * from book. Dbf, where the title is similar to "%basic%"
Display reader information in the reader. Dbf is arranged in the order of registration date.
Select * from reader。 Dbf orders asc (or desc) by application date
Query and display the book numbers, titles and borrowing times of the top three books with the most borrowing times.
Select the book number, title and borrowing times from borrowing. Dbf where the borrowing times are located (select the first three borrowing times from the borrowing books. Dbf orders by borrowing desc).
Look up books. Dbf shows the average price of books.
Select the average (sum) from the book. dbf
Query and count readers. Dbf and shows how many male and female readers there are.
Select gender and count as the number of readers. Dbf is grouped by gender.
Look up the book. Dbf, and display the information of all books whose titles contain the word "program".
Select * from book. Dbf, where the title is similar to "%program%"
Check the statistical books. Dbf, and display the name of the publishing house and the total number of books in each publishing house.
Choose a publishing house and count the total number of books for readers. Group by sex.
Query and display the book numbers and titles of books that have been borrowed at least twice.
Choose the book number and title from the books. Dbf, in which the borrowing times are >; 2
It is very hard. Take it _